#include "delay.h"

#if SYSTEM_SUPPORT_UCOS
#include "includes.h"				
#endif

static u8  fac_us=0;
static u16 fac_ms=0;
#ifdef OS_CRITICAL_METHOD 	

void SysTick_Handler(void)
{				   
	OSIntEnter();		
    OSTimeTick();                    
    OSIntExit();        
}
#endif


void Delay_init()	 
{

#ifdef OS_CRITICAL_METHOD 	
	u32 reload;
#endif
	SysTick_CLKSourceConfig(SysTick_CLKSource_HCLK_Div8);
	fac_us=SystemCoreClock/8000000;	
	 
#ifdef OS_CRITICAL_METHOD 	
	reload=SystemCoreClock/8000000;		  
	reload*=1000000/OS_TICKS_PER_SEC;				
	fac_ms=1000/OS_TICKS_PER_SEC;   
	SysTick->CTRL|=SysTick_CTRL_TICKINT_Msk;   	
	SysTick->LOAD=reload; 		
	SysTick->CTRL|=SysTick_CTRL_ENABLE_Msk;   	   
#else
	fac_ms=(u16)fac_us*1000;
#endif
}								    

#ifdef OS_CRITICAL_METHOD	
		    								   
void delay_us(u32 nus)
{		
	u32 ticks;
	u32 told,tnow,tcnt=0;
	u32 reload=SysTick->LOAD;	    	 
	ticks=nus*fac_us; 			  		 
	tcnt=0;
	told=SysTick->VAL;        
	while(1)
	{
		tnow=SysTick->VAL;	
		if(tnow!=told)
		{	    
			if(tnow<told)tcnt+=told-tnow;
			else tcnt+=reload-tnow+told;	    
			told=tnow;
			if(tcnt>=ticks)break;
		}  
	}; 									    
}

void delay_ms(u16 nms)
{	
	if(OSRunning==TRUE)	    
	{		  
		if(nms>=fac_ms)
		{
   			OSTimeDly(nms/fac_ms);
		}
		nms%=fac_ms;				  
	}
	delay_us((u32)(nms*1000));	
}
#else
		    								   
void delay_us(u32 nus)
{		
	u32 temp;	    	 
	SysTick->LOAD=nus*fac_us; 	  		 
	SysTick->VAL=0x00;        
	SysTick->CTRL|=SysTick_CTRL_ENABLE_Msk ;         
	do
	{
		temp=SysTick->CTRL;
	}
	while(temp&0x01&&!(temp&(1<<16)));  
	SysTick->CTRL&=~SysTick_CTRL_ENABLE_Msk;       
	SysTick->VAL =0X00;        
}

void delay_ms(u16 nms)
{	 		  	  
	u32 temp;		   
	SysTick->LOAD=(u32)nms*fac_ms;
	SysTick->VAL =0x00;    
	SysTick->CTRL|=SysTick_CTRL_ENABLE_Msk ;  
	do
	{
		temp=SysTick->CTRL;
	}
	while(temp&0x01&&!(temp&(1<<16))); 
	SysTick->CTRL&=~SysTick_CTRL_ENABLE_Msk;       
	SysTick->VAL =0X00;        	    
} 
#endif
